Norton b



(No Model.)

AYLOR.

MAGHINIST S GAGE.

Patented Dec. 15, 1891.

lllll U UNITED STATES PATENT OFFICE- v I NORTON B. TAYLOR, OF SHARON,PENNSYLVANIA, ASSIGNOR OF ONE-THIRD TO JOHN F. MCGILLIOUDDY AND CHARLESA. HUETI-IER, OF SAME PLACE.

MACHINISTS GAGE.

SPECIFICATION forming part of Letters Patent No. 465,397, dated December15, 1891.

Application filed June 20, 1891.- Serial No. 396,945. (No model.)

To aZZ whom it may concern.-

Be it known that I, NoRToN B. TAYLOR, a citizen of the United States ofAmerica, re-

' siding at Sharon, in the county of Mercer and State of Pennsylvania,have invented certain new and useful Improvements in aCombination-Tool-Grinding Gage, of which the following is aspecification.

It is the object of my invention to provide a simple form of gage foruse in connection with tools adapted to cut threads in screws. It is myaim to provide a very simple form of gage by which the tool may bereduced to cut the proper size of thread required, the measurement forthis purpose being absolutely accurate, which is not the case when thetool is ground by means of an ordinary rule or scale, as it is veryessential that the measurements be very fine.

In carrying out my invention I provide, in addition to means for gagingthe tool to cut any number of threads to the inch, means for givingtheedges of the tool proper angle for cutting the screw-threads and toalso provide for the proper squaring of the bottom'of the tool when itis desired to cut a thread which is approximately in the shape of atruncated cone having inclined walls and a straight bottom, thusforming, practically, a combination-tool.

In the accompanying drawings, Figure 1 represents a plan view of theimproved tool, and Fig. 2 shows its manner of use, while Fig. 3 showsthe parts detached.

The main part of the tool is shown at A, and is composed of a singlemetal plate having parallel sides and its front end tapering to a point,While its rear end is provided with an angular recess of V shape. Thislatter recess is for the purpose of securing the proper angle for thescrew-thread, and the tool is ground down until it conforms to the shapeof this recess, and in this way the proper angle is secured.

In order to gage the tool so that it will cut a determined number ofthreads to the inch, I have provided, in connection with the main partA, a movable part B, the shank of which is fitted to the grooved face ofthe part A, and is held thereto by means of a set-screw passing througha slot in the part B and through an opening in the part A, and thus thepart B may be adjusted across the face of the part A. The part B has aportion a extending at right angles to the same, and this part a extendsparallel with the length of the part A, and its inner edge bears againstthe edge of the part A, as shown in Fig. 1. The shank of the part B isgraduated, as is also the main part A, along the edge of the groove inwhich the shank moves, and thus any number of threads to the inch may becut by first adjusting the movable part B, so that the specificgraduation on its shank will align with the same graduation on the mainpart, and the space between the adjacent edges of the parts A and a willgive the size of the cutting-edge of the tool, which must be reduced toaccurately fit this space. There it is desired to cut threads which areapproximately in the shape of a truncated cone having a flat spaceat thebottom, instead of terminating in a sharp angle, I have provided aV-shaped notch, as at O, in one of the side walls, the walls of whichare provided with graduations which serve to indicate the differentdepths of the groove to be cut, and when the depth of grooveisascertained the bottom of the tool may be ground off until it alignswith the proper graduation on the wall of the V-shaped notch. After thetool has been properly ground it is then used to cut the thread in theordinary manner.

It will be clear from the foregoing that the gage may be used todetermine the proper size and shape in grinding the tools for thestandard V-shaped thread, the V-shaped notch being used to measure thetool for this purpose, or the tool may be gaged for a square thread bythe angular part B, or for the United States standard thread by thegraduated notch O, the thread being in the form of a truncated cone.

Fig. 2 shows an application of my invention in the setting of a tooltrue with the work, so as to cut a perfectly true thread. The nut 0having been trued up and set in the lathe, the tool D' is placed in thegage, and the gage is then placed against the face of the nut, whichwill insure the placing of the tool in a position true with the nut andWhere it can readily be secured and the gage removed, and the cutting ofthe thread must necessarily be true. tends transversely of the mainpart, the graduated notch is formed in the side of the main part to oneside of the angular part, and the said main part has at one end a deepV-notch, While the other end is pointed. A long bearing-edge is leftalong the side of the main part opposite the parallel portion a, andthis afiords an accurate and certain bearing for truing up the parts, asin Fig. 2.

Having thus described my invention, What I claim is In combination, themain part consisting The angular part exb WVitnesses:

JOHN S. BYCROFT, D. P. STEWART.

